Rigging is not working
Due to the lack of information provided I cannot be entirely sure what the problem is. My guess is that you do not have enough resolution in the cylinder for it to deform.

Select the cylinder and go into edit mode

Add some edgeloop along the height of the cylinder, Ctrl R -&gt; mouse wheel up to increase the number of loops


Go into object mode and select the cylinder and the armature, in that order.

Parent the mesh to the armature, Ctrl P -&gt; With Automatic Weights


Now you can go into pose mode and pose the bones as you desire.